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Microwaves are widely used in fusion-relevant experiments for heating and diagnostic purposes. They suffer, however, from the problem that they have to traverse the plasma boundary, a region where substantial plasma density fluctuations are known to occur. This can significantly distort the beam and thus reduce heating efficiencies which rely on good localization of the injected microwaves (e.g. stabilization of neoclassical tearing modes). Geometrical-optics tools cannot be used to describe the interaction of the small-scale plasma density turbulence and the microwave. Instead, full-wave codes can be used which do not rely on any simplifying assumptions concerning the density variations. Here, we present a full-wave simulation (using the FDTD code IPF-FDMC) of a microwave beam with a frequency of 50 GHz injected onto a plasma with a linearly increasing background density (colour-coded in the video). A layer of turbulent plasma density has been added to, as can be seen from the video. Plotted is also the time-evolution of the absolute value of the wave electric field (the microwave is injected from the right-hand side).

Traditionally, research results presented at scientific conferences are published in conference proceedings. Additionally, an increasing number of conferences are recorded and the videos are subsequently published. In most cases these videos are published by the organisers on commercial platforms or directly on the conference website. Therefore, a systematic search for conference recordings is difficult. Moreover, the videos are often lost after a short time e.g. because the URL changes or external links lead to nowhere. Usually, conference websites are not maintained on a long-term basis and commercial platforms may remove videos or change the conditions for access for a variety of reasons. Finally, to ensure an unproblematic re-use of the material questions of licencing, technical quality and formats have to be solved in advance. In order to prevent the loss of conference recordings the German National Library of Science and Technology (TIB) has developed the AV-Portal. The AV-Portal provides the ideal infrastructure to host, find and reuse scientific videos. It's a single access point for videos from different conferences and years. All videos are assigned a Digital Object Identifier (DOI). These persistent identifiers allow for reliable referencing both as stable online links and as correct citations in scholarly work. In this talk we describe how sharing scientific results via audio-visual media has become an important part of scientific communication and how conference recordings may complement the classical conference proceedings and add new value to the presented research. By discussing the whole process from pre-conference organisation to publishing and archiving the recordings we show pitfalls, best practices and opportunities of recordings for both conference organisers and participants.

Movie S1

The microstructure of polycrystalline ice with a threading solution of brine controls its numerous characteristics, including the ice mechanical properties, ice-atmosphere interactions, sea-ice albedo, and (photo)chemical behavior in/on the ice. Ice samples were previously prepared in laboratories to study various facets of ice-impurities interactions and (photo)reactions to model natural ice-impurities behavior. We examine the impact of the freezing conditions and solute (CsCl used as a proxy for naturally occurring salts) concentrations on the microscopic structure of ice samples via an environmental scanning electron microscope. The method allows us to observe in detail the ice surfaces, namely, the free ice, brine puddles, brine-containing grain boundary grooves, individual ice crystals, and imprints left by entrapped air bubbles at temperatures higher than -25°C. The amount of brine on the external surface is found proportional to the solute concentration and is strongly dependent on the sample preparation method. Time-lapse images in the condition of slight sublimation reveal sub-surface association of air bubbles with brine. With rising temperature (up to – 14 °C), the brine surface coverage increases to remain enhanced during the subsequent cooling and until the final crystallization below the eutectic temperature. The ice recrystallization dynamics identifies the role of surface spikes in retarding the ice boundaries propagation (Zeener pining). The findings thus quantify the amounts of brine exposed to incoming radiation, available for the gas exchange, and influencing other mechanical and optical properties of ice. The results have straightforward implications for artificially prepared and naturally occurring salty ices.

Tomorrowland

FIB-SEM video of two strongly encrusted cable bacteria

FIB-SEM video composed of 501 electron backscatter images. After each image a section of 10 nm was removed and a new section was imaged. The video shows two filaments with a horizontal cross-sectional view along the length of the filament that can be seen on the right at the start of the video. The filament that is visible on the left at the start of the video follows a different direction and therefore the cross-section shows different angles. The thick layer of mineral encrustation appears as a dark seal around the filament, the ridge compartments and the cell content appear white. The encrustation is only found around the filament and not within the periplasmic space. Both filaments are strongly encrusted and the mineral crust of both filaments is partly cemented together which can be observed from 0:06 till 0:26. The encrustation is heterogeneous with an average thickness of ˜500 nm.

Analyzing Mid-Latitude and Arctic Cirrus Clouds by means of large-scale simulations with the Lagrangian model CLaMs-Ice

Simulation of the 1958 Lituya Bay mega-tsunami

TS2The 1958 Lituya Bay landslide-generated mega-tsunami is simulated using the Landslide-HySEA model, a recently developed finite-volume Savage–Hutter shallow water coupled numerical model. Two factors are cru- 5 cial if the main objective of the numerical simulation is to reproduce the maximal run-up with an accurate simulation of the inundated area and a precise recreation of the known trimline of the 1958 mega-tsunami of Lituya Bay: first, the accurate reconstruction of the initial slide and then the choice 10 of a suitable coupled landslide–fluid model able to reproduce how the energy released by the landslide is transmitted to the water and then propagated. Given the numerical model, the choice of parameters appears to be a point of major importance, which leads us to perform a sensitivity analysis. 15 Based on public domain topo-bathymetric data, and on information extracted from the work of Miller (1960), an approximation of Gilbert Inlet topo-bathymetry was set up and used for the numerical simulation of the mega-event. Once optimal model parameters were set, comparisons with ob20 servational data were performed in order to validate the numerical results. In the present work, we demonstrate that a shallow water type of model is able to accurately reproduce such an extreme event as the Lituya Bay mega-tsunami. The resulting numerical simulation is one of the first successful 25 attempts (if not the first) at numerically reproducing, in detail, the main features of this event in a realistic 3-D basin geometry, where no smoothing or other stabilizing factors in the bathymetric data are applied.

Principles of Information Seeking and Retrieval

This is a lecture about the principles of information seeking and retrieval. This lecture was held into the ESSIS 2018 (European Summer School of Information Science) under the EINFOSE european project funded by Erasmus+

The Waried Transport Company - A Chapter from the History of German Technology

In the 1930s, the director of the Waried shipping company took a film camera with him on his travels. It was the era of the Great Depression - and it was also the early days of the National Socialist dictatorship in Germany. Amateur filmmaker Adolf Schneider took movies of ship christenings and launchings, their concomitant celebrations and sea trials. But he also filmed vacation trips and family outings. The movies he made render a portrait of an age and a society in transition, a society heading for a catastrophe of unimaginable proportions about which it obviously had no premonition whatever.

A village in Mexico and Holy Week, a hit-and-run car accident, and a tequila-drinking police chief – and a film team from Göttingen at the heart of it all. Six binder files and reels and reels of film material tell the adventure of an expedition to Mexico 30 years ago. With the “unearthing” of an ethnological film treasure, the preliminary end of the tale can be told in 2018. A contribution to the 2018 World Day for Audiovisual Heritage.